Refrigerated display stand



A ril 26, 1938.

w. L. STEWART 2,115,048

REFRIGERAT ED DI SPLAY STAND Filed Feb. 24, 1936 INVENTOR. I 1/07/40 05. final an- ATTORNEY);

Patented Apr. 26, 1938 I UNITED sass PATENT OFFICE,

REFRIGERATED,DISPLAY STAND William L. Stewart, Cleveland, Ohio Application February 24, 1936, Serial No. 65,437

4 Claims.

This invention relates to a display stand suitable for use in restaurants, cafeterias, markets and other situations where food must be kept cold and fresh and at the same time kept in public sight and in condition to present a fresh and attractive appearance. A feature of the invention consists of so arranging and operating the stand that the stand will carry a heavy coating of white frost, which thus forms a contrasting background having an ornamental efiect enhancing the attractive and fresh appearance of the articles displayed thereon, besides the utilitarian purpose of preservation. Such a stand is particularly intended for the display of salads and fresh fruits in cafeterias, although not limited to such use.

One difficulty to be overcome in constructing a stand for such use is that of keeping the top horizontal surface thoroughly frosted, another is that of accomplishing circulation of air over the displayed food so as to keep it fresh. By my invention I am enabled to overcome both these difficulties and avoid the necessity for putting the stand into an air-tight case. If glass screens or covers are required by local sanitary regulations where the stand is used, such covering can be arranged with liberal air circulation openings.

, A further aim of the invention is to properly humidify the air circulating down over the material on the successive levels of the display stand, without use of free liquid or visible vapor.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims.

The annexed drawing and the following description set forth in detail certain structure embodying the invention, such disclosed means constituting, however, but one of various structural forms in which the principle of the invention may be used.

In said annexed drawing:

Fig. 1 is a perspective view of a preferred form of the stand;

Fig. 2 is a transverse vertical section therethrough, but including a slight modification.

In the form shown in Fig. 1, no drainage provisions are illustrated, it being assumed that the table on which this form will be placed will include a suitable shallow gutter or the like at the bottom. In Fig. 2 a drain is shown associated with the display stand.

A shape which will utilize the inherent advantages of my invention is that of a step pyramid, Figs. 1 and 2. This shape provides ample shelf space, raises the displayed articles in successive rows where they can readily be seen and reached, enables the entire horizontal area occupied by the stand to be used for the placing of articles thereon, minimizes waste refrigerating effect of the vertical surfaces, and causes a cascade of cold air to pass down gently over-the displayed articles.

In the illustrative embodiment, the stand comprises a closed vessel H preferably of non-corrosive metal, such as stainless steel, Monel metal, or other material having suitable characteristics. The stand as shown in Fig. 1 is intended to represent a size which can be set upon a table or counter so that the lowest horizontal step I: will be about ordinary table height above the floor. Such support is not shown since it forms no part of the invention. It will be understood of course that the principles of the invention are not affected by changes in size; myrefrigerated display stand may be large or small according to circumstances, and may also be varied in shape within the principles of my invention.

Inasmuch as there is no purpose in having the lowermost verticallsurface l8 frosted, this surface, as well as the bottom It, is protected by a layer of insulating. material I5, between the outer walls l3, l4 and inner walls l6, l1. Thus access of the coolant l8 to the insulation is impossible. In the present embodiment the intention is to use a liquid coolant such as brine, thisliquid being in turn kept cold by refrigerating Cells [9 within the stand.

Access .to the coils I9 is had through the top 20, and also, if desired, through a side or end, for example by liquid-tight panels such as 2| in the lowest vertical surfaces. These. panels 1! may be of any well known construction and form in efiect a portion of the double metallic wall l3, l6 and its intermediate insulating layer ii. The detail of the panel construction forms no part of the invention. Such openings and their closures are well known and consequently not otherwise illustrated than as in Fig. 1.

The liquid level 22 will be carried almost to the undersurface of the top it. In order to give further access to the interior, and as a convenient method of construction, the top it preferably consists onLv ofa single plate which rests on the upper edges of the topmost vertical walls 23. Inasmuch as the interior is not under pressure at the top, and inasmuch as the top plate can be removed from time to time to wipe the inner vertical surfaces, thus preventing any creeping of salt or other matter-which might show on the outside, it win ordinarily be sufllcient to rest the top-in place by gravity alone, although additional fastening means may of course be used if needed.

To position the top plate 20 accurately, flanges such as 24 are provided on its under surface a proper distance within the edges. These may be integral with the top plate, or welded or otherwise secured thereto in mechanical and thermal contact.

surfaces It will be concealed from view. Where such is the case there is no objection to moisture, due to melting frost, trickling down over these. Where they are to be exposed, or where for any reason they should be kept dry, a molding I213 may be provided around the lowest horizontal surface IIA, as shown in Fig. 2, and drainage provided by openings such as 26 and drain tubes such as 21 at the necessary intervals.

In operation it is contemplated to run the display stand with a temperature sufliciently low to cause the accumulation of a layer of thick white frost on all the metal parts above the surfaces l3. Inasmuch as all the surfaces above l3, ex-

cept the top plate 20 are of metal behind which the brine is directly in contact, and the top plate 20 is thoroughly cooled by its flanges in the brine, this frost will form and stay, giving the entire surface upon which the food rests a pure white velvety coating, inherently suggestive of cleanliness, coolness and freshness. The step construction disposes this velvety frost coating both beneath and behind the displayed foods, forming a background and a color contrast against which the natural colors of leaves, fruits, and other food products are displayed to great advantage.

The frost does not melt to any serious extent if the coolant is kept at a sufllciently low temperature by use of the cooling coils. However,

there is some evaporation of moisture from the surface of the frost, which humidiiies the air close to the surface. By reason of the stepped construction, this humidified cold air will flow down from the top level along the sides and over each successive level, thus keeping a constant gentle current of cold air passing over the articles on the successive levels and to some extent blanketing such articles. It will be understood, however, that this blanketing effect is not by a stationary body of air but by a cascade of air in continuous gentle downward motion, thus contributing very materially to keeping the food on display fresh as well as cold. The removal of trays or other articles from the steps does not affect this circulation.

A further advantage is that by my improved display stand leafy vegetables, salads and similar articles which must be kept humidified can be so humidified by a circulation of cold air moistened by the frost which, due to the construction of the stand, is automatic. This avoids the need for sprays, which have sometimes been used for this purpose, but which are objectionable as requiring arrangements to be made for draining free liquid, and are also objectionable as excessively humidifying the air of the room.

Although my invention is not limited to the particular form shown, the form shown has advantages in that it accomplishes complete utilization for display purposes of all the horizontal space occupied by the stand, and also provides display space at the ends as well as at the sides. In this last respect, the step pyramid avoids any vertical surfaces which do not have display shelves in front of them.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the structure herein disclosed, provided the means stated I by any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out'and distinctly claim as my invention:

1. A refrigerating display stand comprising in combination a hollow casing of heat-conducting material, generally receding from bottom to top, said casing including shelves and a top of aggregate area equal to the base area of the stand, risers extending between the shelves and each connecting the front edge of one shelf to the rear edge of the next lower shelf, the shelf and risers having exposed heat-conducting surfaces and providing a step-like formation for the support of articles to be cooled, said stand being liquidtight substantially to the top and adapted to be filled with liquid, and a cooling coil in the space for said liquid.

2. A refrigerating display stand comprising a hollow step pyramid including steps and risers of heat-conducting material outwardly exposed, and a. top closure upon the uppermost: riser, said stand being adapted to contain a cooling liquid therein, the top of said liquid being adapted to stand above the bottom of the top riser of the pyramid, and fins on the under surface of said top closure adapted to reach into said liquid.

3. A refrigerating display stand comprising a hollow casing, said casing being formed into shelves rising one above the other in successively receding step-like formation, each shelf presenting an extended area for the support of goods in position to be reached without disturbing goods on adjacent shelves, said shelves being connected by risers, the shelves and risers being formed of material of high heat-conductivity, and a refrigerant within said stand directly in contact with said shelves and risers.

4. A refrigerating display stand comprising a hollow casing, said casing being formed into substantially flat shelves rising one above the other in successively receding step-like formation, each shelf presenting an extended area for the support of goods in position to be treated without disturbing goods on adjacent shelves, said shelves being connected by risers, the shelves and risers being formed of outwardly-exposed material of high heat-conductivity, a refrigerant within said stand directly in contact with said shelves and risers, and means within said stand for abstracting heat from said refrigerant.

CERTIFICATE OF CORRECTION. Patent No. 2,1 1 ,ou3. 1 A r-1126, 19 8.

wILLIAM L. STEWART.

It is hereby certified thet error appears in the printed specification of the above numbered patent requiring correction as follows; Page 2, second column, line 61, claim for the word "treated" read reached; and that the said Letters Patent should beread with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and 'sealed this Zhth day of May, A. D. 1958;

Hem"; Van Arsdale, (5 Acting Commie sioner of Patents. 

